This invention relates to sanitary articles for absorbing body fluids, and more particularly to sanitary articles worn by women for absorbing and containing body fluids produced during menstruation.
A number of sanitary articles have been developed for absorbing and containing body fluids produced during menstruation. A commonly-used type of sanitary article is the sanitary napkin which is worn between a woman's body and an undergarment to protect the undergarment and adjacent garments. A typical sanitary napkin consists of an inner layer of absorbent material which is worn next to the body, and an outer barrier layer which is worn between the absorbent layer and the user's undergarment. The outer barrier layer is constructed of a water-proof material to prevent fluid absorbed by the inner layer from leaking or spreading by capillary action to other garments.
Existing feminine sanitary napkins have a variety of significant disadvantages which cause discomfort and inconvenience for users. One problem with many existing napkins is that they lack adequate absorbent capacity to permit the user to wear the napkin for an acceptable length of time before replacing it with a fresh napkin. When the user's rate of fluid discharge exceeds the capacity of the napkin, the fluid may leak to and soil adjacent garments. This causes significant embarrassment and inconvenience for the user. Even when the absorbed fluid does not actually spread to another garment, some fluid may still be released from the layer back onto the user's body, causing discomfort and irritation. In addition, such body fluids may produce an undesirable odor when not properly contained.
In order to solve the capacity problem, sanitary napkins have been developed containing larger quantities of absorbent materials. A problem with such larger-capacity sanitary napkins is that they are relatively bulky. Such napkins are inconvenient for many users because their larger size makes them inconvenient to store, carry and apply. In addition, because of the additional absorbent material, they are generally thicker than previous napkins and their presence under the user's clothing is more difficult to conceal.
Another problem with significantly larger capacity napkins is that once the napkin has absorbed a substantial amount of fluid, it is difficult to prevent the napkin from releasing some of the absorbed fluid back to the user's body as the user goes about the normal activities of daily life. When the user conducts such dynamic activities as walking and bending over, the user's body may compress the absorbent layer, thereby forcing some of the absorbed fluid to be released. Thus, an increase in the amount of absorbent material in a napkin may not result in a proportional increase in either the capacity or the wear time in actual use.
In addition, special "super-absorbent materials have been developed which have higher absorbent capacity than previously used materials. Still other sanitary napkins have been developed with a top sheet to prevent the fluids, once absorbed, from being released again back to the user's body. However, these napkins still have a limited time of use and require relatively frequent replacement.
A further problem with existing sanitary napkins is disposal of soiled napkins and application of fresh napkins. Typically, sanitary napkins are constructed of materials which cause disruptions in normal plumbing systems and therefore cannot be disposed of in toilets. Thus, in almost every case, the user must dispose of the soiled napkin in an ordinary refuse receptacle. The problem of proper disposal of the soiled napkin causes embarrassment for some users. For example, when using a public restroom, the user may be unable to prevent others from viewing the user's disposal of the napkin. Users may also have health concerns in public facilities due to potential exposure to the discarded napkins of other users. When visiting the private home of another, the user may not wish to dispose of the napkin in a receptacle which is only occasionally emptied. Similar privacy problems attend application of fresh napkins.